Ok, here's the low down on this problem. We were supplied with a honeywell 90 degree position sensor. It looks just like a pot but it draws a bit of current. It seems there are models that are made for this sensor and others that use a common pot. Due to the current it draws this device was pulling down the pot high signal and pulling up the pot low sensor so the wiper voltage at J4-7 was all wrong. Either get a pot or rewire the positive and negative of the sensor to +ve on J4-15 and negative on J4-16. Leave the wiper on J4-7. Then you need to measure the value in the handset monitor and program the values for left centre and right into the controller. This is for models with Curtis controllers 1310-5310 and 2 sepex controllers.